Chewing gums are generally comprised of chewing gum base such as chicle, its substitutes, mixtures thereof and the like. Incorporated within this gum base may be plasticizers or softeners to improve the consistency and texture of the gum, flavors and sweetening agents such as corn syrup or for sugarless gums, artificial sweeteners.
All commercially available gums are classified as either "sugar" or "sugarless" confections. A typical sugar gum is Wrigley's Chewing Gum manufactured by the William Wrigley, Jr., Company, Chicago, Illinois. An example of a sugarless chewing gum is Trident, manufactured by the Warner-Lambert Company, Morris Plains, New Jersey. These gums have a tendency to become brittle on storage at low relative humidities (below about 55% RH) which is the condition that prevails in many locations where gum is sold. The development of brittleness which detracts from the good chewing quality of the gum is associated with loss of moisture to the atmosphere. Chewing gum is typically manufactured and packaged in a controlled environment of about 70.degree. F. at about 57% relative humidity. Under these conditions the gum is in equilibration with the atmosphere, that is, the gum neither gains nor loses moisture. Gum wrappers or packaging represent a substantial portion of the cost of manufacture in the processing of chewing gum. Particularly, each stick of gum is usually covered by at least three or four separate layers of wrapping or packaging material before it is put in the stream of commerce. Such packaging slows down but does not alleviate the loss of moisture unless expensive and perfect (i.e., free from pinholes, a condition which is all but impossible to achieve in practice) packaging materials are used.
It would, therefore, be highly desirable if a chewing gum composition could be devised which would not become brittle upon storage at low relative humidities.